IB/mad: IBoE supports only QP1 (no QP0)

Since IBoE is using Ethernet as its link layer, there is no central
management entity so there is need for QP0.  QP1 is still needed since
it handles communications between CM agents.  This patch will skip QP0
and create only QP1 for IBoE ports.

Signed-off-by: Eli Cohen <eli@mellanox.co.il>
Signed-off-by: Roland Dreier <rolandd@cisco.com>